Indenting press for the hollow arbor of a cannon pinion



J. KOCHIS May 26, 1953 INDENI'ING PRESS FOR THE HOLLOW ARBOR OF" A CANNON PINION Filed June 19, 1950 John Koch/s INVENTOR.

Patented May 26, 1953 UNITED STATES PATENT OFFICE INDENTIN G PRESS FOR THE HOLLOW ARBOR OF A CANNON PINION John Kochis, Melvindale, Mich.

Application June 19, 1950, Serial No. 168,881

1 Claim. 1

This invention relates to a press for indenting the hollow arbor of the cannon pinion of a watch, so as to set up proper friction between such arbor and its driving shaft after such arbor has become loose from wear.

The primary object of the invention is to provide a simple and efficient press of the above kind by means of which a dent of predetermined depth may be quickly provided in the cannon pinion arbor even though the bore of said arbor may, as is often the case, be closed at the outer end of the latter.

Another object is to provide a press of the above kind including a rest for the arbor, a hand lever carrying an indenting tool and adapted to be struck a blow with a hammer to perform the denting operation, and adjustable means for limiting the movement of the lever and tool thereon when subjected to said blow so as to provide a dent of such predetermined depth in the arbor as to set up proper friction between the latter and its driving shaft.

An embodiment of the invention is shown in the accompanying drawing, in which:

Figure 1 is a top plan view of the press;

Figure 2 is a vertical longitudinal section taken on the line 22 of Figure 1;

Figure 3 is a vertical transverse section taken on the line 3-3 of Figure 1; and

Figure 4 is a view showing a cannon pinion and its arbor in central longitudinal section and mounted on its driving shaft.

The present press is used to indent, as at 5, the hollow arbor 6 (see Fig. 4) which has the cannon pinion l fixed on the inner end thereof and is adapted to have an indicating hand pressed onto the outer end of the same. In some cases, the bore of arbor 6 is closed as at 8 at its outer end. In practice, the arbor 6 receives a driving shaft 9 having a reduced tapered in termediate portion 10 forming a shouldered recess which receives the indentation 5 to provide a frictional driving connection between shaft 9 and arbor 6, whereby the latter may be forcibly turned relative to shaft 9 to set the minute hand. Shaft carries the usual driven gear ll. When the arbor 6 becomes loose from wear, the indentation must be accurately deepened to a predetermined extent so as to again set up proper friction between arbor 6 and shaft 9. For several reasons, this is a time-consuming and difficult thing to do with ordinary tools, and the present press has been designed to quickly and accurately perform the desired operation.

As shown, the press comprises an elongated base block I2 having integral posts 13 and M of similar height respectively projecting upwardly from the rear and front ends thereof. The posts have bifurcated upper ends, and one end of a hand lever I5 is pivoted between the furcations of post l3 by a cross-pin [6, the lever 15 being adapted for snug reception near its other end between the furcations of post 14 when said lever is swung downwardly to a substantially horizontal position. The lever I5 is provided intermediate its ends with a vertical opening l1 adapted for snug reception of the shank or stem 18 of an indenting tool having a chisel-type bit 19 and provided with a stop or thrust flange 20 adapted to abut the under side of lever l5. Suitable means, such as a set screw 2|, may be provided to removably secure the shank [8 in place.

The base block is provided with a vertical opening 2'2 for snug reception of the shank or stump 23 of a work rest having a tapered anvil 24 provided with an end recess 25 in which the workpiece, the arbor 6 here, is adapted to be seated during the indenting operation. The work rest has a stop or thrust flange 26 adapted to abut the upper side of the base block.

Extending through the base block 12 and post It in a plane between the furcations of said post is a threaded opening 21 in which is screwed an adjustable stop screw 28 for adjustably limiting the downward movement of lever I5.

In using the press, lever I5 is raised, arbor 6 is seated at the porper point in recess 25, and then lever I5 is lowered to contact the bit IS with said arbor, the lever i5 being then spaced from the surface of post I4 between its furcations. Screw 28 is then adjusted upwardly until its upper end is beyond this surface and about .002 or .003 of an inch from lever l5. Lever I5 is then struck at the point a by means of a hammer so that it is driven against the screw 28 and the indentation 5 is given the required depth.

The construction, operation and advantages of the invention will be apparent to those skilled in the art in view of the above.

Having described the claimed as new is:

For use by watchmakers, a device for holding and indenting a cannon pinion arbor comprising a base having upstanding posts of similar heights projecting upwardly from rear and front ends of the base, the upper ends of said posts being bifurcated, a hand lever pivoted at one end between the furcations of the rear post, the other end of said lever being adapted to be invention, what is moved to an operating position between the furcations on the upper end of the front post, said base being provided between said posts with opening means, a stump fitted removably into said opening means and having an upstanding anvil underlying the center portion of said lever, a depending chisel type indenting tool mounted removably on the intermediate portion of the lever and opposed to said anvil, said front post having a vertical screw threaded bore opening at its upper end between the iurcations atop said front post, and a setscrew adjustably mounted in said bore and having its upper end cooperable References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 894,726 Corbin July 28, 1850 2,144,540 Lindgren Jan. 17, 1939 2,451,378 Bloom Oct. 12, 1948 

